Tool slide and dwell mechanism



June 29, 1937. E. P. BULLARD, 3D 2,035,692

TOOL SLIDE AND DWELL MECHANISM .Fi led Jan. 18, 1936 4 Sheet -Sheet 1 IIIIIW ge iaeam INVYEN'TOIYC. EDW RD PBUL Lq lZZ June 29 1937.

E. P. BULLARD, so

TOOL SLIDE AND DWELL MECHANISM Filed Jan. 18, 1936 4 Sheets-Sheet 2 V INVENTOR. EbWARD PBL/LLARQZZZ BY 6 A'TTOIJVEYS.

June 29, 1937. .E. P. BULLARD, 30

TOOD SLIDE 'AND DWELL MECHANISM mm; Jan. 18, 1936 4 Shets-Sheet s INVENTOR. EDWARD P-BuL LARDJZZ 5/9 I" ATT RNW 40 Present invention shown in Patented June 29,1931

UNITED STATES 2,085,892 I :roor. snmnann nwim. MECHANISM mm P. Billiard, In, Fair-field, Oonm, assignor toTheBullard connect! Application January 18, 1936', Serial No. 59,731

Company, a corporation of 17 Claims. (CL 82-21) The invention relates to machine tool slides and dwell mechanisms therefor, and is adapted particularly to-machine too of the lathe type in which the tool slide acts by reciprocation pply and'remove'the cutting tools to a-rotating work p ece.

. One of the objects of the present invention is to provide a novel, simpleand improved construction which will lend itself to economic manufacture, to simplicity inoperation and which will act with smoothness and precision.

Another object is to provide a new and improved tool slide particularly designed for reciprocation in response to the rotation of a feed 5 screw and which has incorporated therein a v positive stop mechanism for limiting the movement of theslide in response to the rotation of the. screw.

. Another important object is the provision of a tool slide mechanism which. will incorporate therein a simple dwell m which will permit the slide to remain stationaryyafter it hasreached a'predetermined position during further rotation of the screw.

'25 Another object is. to provide a slide mechanism in which the dwell period. may be readily adjusted to compensate for the particular requirements of machine operations. v

Another object of the invention is to provide a positive stop for the feeding of a tool head and, i at the same time, allow the drive means to con tinue to operate for a period prior to'the stopping or reversing of thedrive means.

Numerous other objects and features of the present invention will be apparent from a consideration of thefollowing specification taken in conjunction with the'accompanying in which:

Flgure'l is. a front elevation of one formal the conjunction with a work spindle of a lathe type of machine tool, part of the structure being broken away. Figure 2 is a transverse section taken on the lines {-2 of Idgure -1.

,5- l'igure3isasimilarsection'showlngtheparts in a diil'erent positiomand' l igure Qisatopplan viewastaken onthelines 4-4 of Figure 1.

in which the tool feed is by'the rotation of-a threaded feed screw. The invention is adapted for single or multiple tooihead machines, but is 55 particularly applicable to multiple spindle st'a-' rectilinear and r of the work. ,It is obvious, however, thatthe 5 A ,tion type machines. The structural embodiment of the invention is here adapted as applicable to a simple tool slide in which the tool movement .is parallel to the axis of rotation therethrough, and with which the element may 15 have threaded engagement whereby the rotation of the screw will cause axial movement of the actuating element.

The releasable latching mechanism includes-a pair of cooperating actuating mechanism 'nd another carried by the saddle, the cam s faces being normally se-v cured against movem nt, with respect to'each other, by a trigger mechanism. An adjustable, positive stop is provided to determine the down- 25 ward movement of the saddle and, prior to-engagement thereof, the trigger mechanism is adapted to be actuated thereby to release the normal engagement of the cams, thereby un'latching the actuating mechanism from the saddle and V '30 permitting relative movement thereof withrespect to the saddle. By adjustment of the spring element, the length of movement of the cam may be varied, thus to' positively limit the amountof lost motion betweenthe slide and the feed screw. 35

In-lathe operations, such lost motion or dwell movement is an advantagecin that, since it is usual to operate the spindle inconjunction with the feed drive of the tool, it is advisable for the spindle to make one ormore revolutions at the 40 end of the cutting action while the tool is still engaged with the work so that the tool will not be left in the cut of the work..- It will be hereinafter seen that the present invention accommodates this requirement in a simple, eflfeotive and efllcient manner without incorporating in the structure weakness anduncontrolled lost motion v which would otherwiserender the structure faulty -While the invention is broadly'applicable to;

various types of machine tools, it is particularly designed for use in conjunction with a machine saddle body It upon whieh'mav'be secured one s, one carried by the go i or more suitable tool holding members, as indi- The column II is further provided with a recessed channel II in which an adjustable stopsupporting block '20 is mounted, slight adjustment of which is provided for by an adjusting screw 22 and lock nuts 24. The stop supporting block is further provided with notches 25 and threadedapertures II, which receive a stop piece ll keyed and bored to be selectively received within a selective notch and to be secured by the medium of a securing screw It.

As shown in Figure 1, the arrangement is adapted to provide for the reciprocation ofv the saddle or slide in a path parallel to the axis of a work'carrying spindle 8|, which rotates a work piece 32. A tool 33 is mounted in the tool holder l8 and is adapted to move in an axial direction to eflect a turning of 'the work piece.

The body of the saddle II has a central recess within which is mounted an actuating member 86 shown partially in sections in Figures 2 and 3, and within the actuating member is secured an operating nut) through themedium of securing screws 35, whereby, upon rotation of a feed screw 31, the nut will. act to vertically raise or lower the actuating member in accordance with the direction of rotation of the screw; rotative movement of the nut and actuating member, with respect to the slide, being precluded. by the inter-fitting relation thereof. The side of the actuating member I. is provided with a flange 38 extending into an accommodating recess of the saddle, the lower end of the flange is provided with an inclined camming surface it, which is maintained in contact with a cooperating, similarly" inclined, surface 40 of a spring-urged latching bolt I I, which is preferably .through the body of the or rectangular crow-section, as indicated in Figure'l of the drawings, and

saddle ll. The bolt ll is normally urged inwardly by a spring 43 acting upon the bolt head 45, its tension being adjustable by adjustment of a screw cap 1.

The lower side o the bolt II is provided with a recess l2, adapted to'receive a head H of a which is slidable spring-urged plunger 40 which is normally urged upwardly by a spring 48. The plunger 46 is provided with an opening I! to receive therein a head 54 of a trip lever I which is freely pivoted upon a pin it. The opposite end 51 of the trip lever is held in engagement with the upper end of a trip pin 5|, mounted to extend through and protrude fromthe lower portion of the for limited, free movement therethrough,the limitation being provided by the cooperation of a recess 59 thereof and a set screw I.

The downward movement of the saddle or the slide, with respect to the actuating element, is adiustably limited by a set screw 62, adjustably extending through atop flange of the slide and adapted to limit the downward movement of the slide by engagement with a stop lug 64, mounted in the actuating member 36, as shown in Figures 2 and 3.

In the operation of the device, the normal position of the parts is shown'in Figure 2, in which the actuating element is latched to the saddle or slide,- and the cooperation of the set screw 52 and lug 04 act in conjunction with the cooperative action of the angled surfaces to cause either directional rotation of the feed screw to,

move the saddle with the actuating member in either direction. At the termination of the pressing its spring 43 until the coils thereof come into contact to act as a definite limit for the downward movement of the element with respect to the slide.

The timing of the feed works for the screw may also be adjusted so as to stop the movement of the screw to determine the amount of lost motion between the element and the slide so that such movement of the screw may stop prior to the limit of compression of the spring. A deilniteelimit is provided by the adjustment of the spring.- .When the feed screw is reversed, the action starts from the position of the part, as shown in Figure 3. The actuating element moves upwardly with respect to the slide, the plunger moves inwardly and the lug engages the set screw, thus lifting the slide, whereupon, the latch plunger moves downwardly through the bottom of the slide and the plunger 46 engages- -means for retaining said surfaces against camming action to latch the saddle and element for movement together and means for releasing ,said surfaces for camming action to permit the element to move with respect to the saddle.

2. In a tool mechanism for machine-tools, a saddle, an operating element therefor, cooperating cam surfaces on said element and said saddle, means for retaining said surfaces against camming action to latch the saddle and element for movement together, means for releasing said surfaces for camming action to permit the element to move with respect to the saddle and means for limiting the amount of such relative movement. I Y

3. In a tool mechanism for machine tools, a saddle, an operating element therefor, cooperating cam surfaces on said element and said saddle, means for retaining said surfaces against camming action to latch the saddle and element for movement together, means for releasing said surfaces for camming action to permit the element to move withrespect to the saddle and means for adjustably limiting the amount of such relative movement. 1

4. In atool mechanism for machine tools,-a saddle, an operating element therefor, cooperating cam surfaces on said element and. said saddle, means for retaining said surfaces against camming action to latch the saddle and element for movement together, means for releasing said surfaces for camming action to permit the element to move with respect to the saddle and a positive stop for limiting the movement of the saddle surface carri face mounted to release the saddle- I the amount of camming movement of the slide to I the saddle, an

.surface over which said saddle operable to release said surfaces to permit said respective movement. f

5. In a tool slide, an actuating member, a cam surface carriedthereby, a tool slide and a cam surface mounted in said slide, being releasably retained in contact with the other cam surface whereby the cooperation of said sur-' faces will effect movement of said slide with said element during the re ntion of the releasable 6. In a tool slide, an actuating member, a camsurface carried thereb a tool slide, a camsurface mounted in said slide, one of said surfaces being releasably retained in contact withthe other cam surface whereby the cooperation of said surfaces will effect movement of said slide with said element during the retention of the releasable surface and means operable uponpredetermined release said releasable surface to permitrelative movement of the operating element with to the slide.

7. In a tool slide, an actuating member, a cam thereby, a tool slide, a cam surin saidslide,one of saidsurfaces being releasably re in contact with the other cam surface whereby the cooperation of said surfaces will eifectmovement of said slide with said element during the retention of the releasable surface, means operable ,upon predetermined movement of the slide to release said releasable siu'face to permit relative movement of the operating element with respect to the slide and means for adjustably limiting the amount of said relative movement.

a. In a machine tool; a feed screw, a saddle, a

surface over which said saddle moves, a positive stop on said surface'jo limitthe movement of operating element within the sad-' dleforconnecting the saddle for rectilinear movement in response to rotation of the screw and means releasably connecting said element and saddle, said means being operable by said stop to release the saddle from the element. 7

9. In a machine tool, a'feed screw, a saddle, a moves-a positive stop on said surface to limitrthe movement of the saddle, an operating element within the saddle for connecting the saddle for ment in response to rotation means releasably of the screw and saddle, said meansbeing operable in said stop from the element and including a member adapted tobe in nsetorelative movement and the saddle. V

lcrewta saddle.

10. In a machine tool, a feed a surface over which a tivestopiiifsaid movement operating element movement in response to rotatiimjof the screw, means releasably saidrclunent and eluding a member adapted to he mined in response to relative movement between the element and the saddle and means for adiustahly limiting 11. In amachine tool, afeedscrewnn element be r iprocated-in response to the rotation thereof,asaddle;meansforreleasahly connecting said element -and.mddle, a positive stopforsaidsaddlaalatchoperable by saidstop to release'said element from said oneofsaidsurfaces move- 7 respective movement between said element and 'a surface on said element.

' carried by said element and engageable with a separate surface of said saddle for lifting said saddle upon upward movementof said element.

:13. In a machine tool, a feed screw, an element "rectilinear-1y movable in response to the rotation- -of the screw, a saddle, a surface on said element co-acting with the surface 'on said saddle for moving the saddle downwardly upon downward movement of said element and a separate surface, carried by said element and engageable with a separate surface of said saddle, for lifting said saddle upon upward movement of .said element, said surfaces being arranged to permit movement of said element with respect to said saddle.

- 14. In a machine tool, a feed screw, an element rectilinearly movable in response to the rotation of the screw, a'saddle, a surface on said element co-aeting with the surface on said saddle for moving the saddle downwardly upon downward movement of said ,element' and a separate surface, carried by said element and engageable of the screw, a-saddle, a surface on said element ,co-acting with the surface on said saddle for moving the'saddle downwardly upon downward movement of said element and a separate surface, carried by said element and engageable with a separate surface of'said saddle,,for lifting said saddle upon upward movement of saidelement, said surfacesbeing arranged to permit movement of said element with respect to said saddle and one of said elements being movable to permit movement of said element with respect to said 16. In rectilinearly movable in response to the rotation of the screw, a saddle. asurface on said element co-acting with the surface of said saddle for moving the saddle downwardly upon downward movement of said, element and a separate surface, carried by said element and engageable with a machine tool, a feed screw, an element a separate surface of said'saddle, for lifting said a saddle upon upward movement of said element, said surfaces being arranged to permit movement of said element with respect to said saddle and one of said elements being movable to permit movement of said element with respect to said saddle and means operable upon predetermined movement of said saddle to release said movable l'l. In a machine tool,' a feed screw, an elementrectilinearly movable in response to the rotation of the screw, a saddle,'a surface on said element co-acting' with the surface of said saddle for movingthe saddle downwardly upon downwa d movement of said element and a separate surface, car- "rled by said element and engageable with a separate surface of said saddle, for lifting said saddle upon upward movement of saidelement, said surfaces being arranged to permit movement of said element with respect to said saddle and one of said elements being movable to permit 5 movement of said element with respect to said saddle, means operable upon predetermined movement of said saddle to release said movable surface and means, operable through the cooperation of said surfaces, to move one with respect to the other after the release of one of the surfaces.

' EDWARD P. BULLARD, III. 

